Lazzarini also noted that the remaining public services in besieged Gaza are collapsing fast and that people in the strip gripped by war now face food shortages.

The head of the UN agency for Palestinian refugees criticized the international community, saying it "seems to have turned its back on Gaza."

Speaking to reporters in Jerusalem, the UNRWA chief said the agency was very short on fuel in Gaza and needed about 160,000 litres of fuel a day to supply hospitals and bakeries.

UNRWA staffers in Gaza are saying "their operations are crumbing" and "for the first time ever, they report that now people are hungry," Lazzarini said. "Civil order is collapsing."

Asked how long supplies will last, the UNRWA chief said: "Certainly no more than a few days.”

He added that 57 employees of the agency in Gaza have been killed since the outbreak of the war on 7 October.

"To equal Gaza with Hamas is very dangerous and misleading," he said. "We cannot turn a blind eye to this human tragedy"

On Monday, a UN special investigator said Israel is required under international law to protect civilians and is banned from targeting schools, hospitals, and people fleeing harm.

Fionnuala Ní Aoláin, the special rapporteur on protecting human rights while countering terrorism, told a UN news conference that when these rules of international humanitarian law are breached, "we are also in the territory of war crimes."

Thousands of Gaza residents have sought shelter at UNRWA facilities since Israel launched relentless airstrikes in the Gaza Strip three weeks ago.

More than 7,000 Palestinians were killed and more than 19,000 were wounded in those airstrikes, according to the Palestinian health ministry in Gaza.

Israel has cut off all supplies of fuel, water, food, and electricity to 2.3 million Palestinians under bombardment in the strip.